Enzymatic reaction kinetics within pickering emulsions through progress-curve analysis

Pickering emulsions are attracting increasing attention in biphasic biocatalysis because their particle-stabilized interfaces provide a large contact area between enzymes in the aqueous phase and water-insoluble substrates. Despite growing interest, a comprehensive kinetic framework for enzymatic reactions in Pickering emulsions remains lacking. Here, a progress-curve-based kinetic description of a hydrolysis reaction is presented for the first time and compared with both a single-phase system and a particle-free biphasic system. Transitioning from an aqueous single-phase system to a biphasic system the maximum reaction velocity v<inf>max</inf> increased threefold, while the apparent Michaelis–Menten constant increased by four orders of magnitude, indicating significant interfacial mass-transfer contributions. Notably, Michaelis–Menten kinetics derived from initial rates failed to predict product formation at elevated concentrations due to product inhibition. Direct fitting of integrated rate equations to full progress curves enabled efficient parameter estimation and captured product inhibition while substantially reducing experimental effort compared to conventional initial-rate analysis. Both competitive and non-competitive inhibition models adequately described the data. Comparison with a particle-free biphasic system revealed similar kinetics at high stirring rates; however, under reduced energy input, the Pickering emulsion retained its kinetic parameters and activity, whereas the biphasic system became mass-transfer limited. Overall, this study establishes macrokinetic parameters for Pickering emulsions using progress-curve analysis and demonstrates their advantages under low-stirring conditions, providing a basis for process development.

Subjects

Biocatalysis

Biphasic

Enzyme kinetics

Pickering emulsion

Progress curve

DDC Class

660.2: Chemical Engineering

Lizenz

https://creativecommons.org/licenses/by/4.0/

Publication version

publishedVersion

Name

1-s2.0-S1385894726070725-main.pdf

Type

Main Article

Size

2.82 MB

Format

Adobe PDF

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Enzymatic reaction kinetics within pickering emulsions through progress-curve analysis